CINCINNATI -- Sullen and downtrodden after fumbling away a victory they had firmly in their grasp, the Miami Dolphins tried to convince us, and maybe themselves, that everything would be OK and that they could quickly switch focus to Week 6 against the Chicago Bears after Sunday’s meltdown in Cincinnati.

But there doesn’t appear to be an easy fix to the team’s biggest problem: The Dolphins' offense has yet to figure out its identity, and in turn, it has done more harm than good.

That is why it’s hard to trust that the Dolphins aren't still stuck in mediocrity, their familiar residence for much of the past two decades.

The Dolphins' big Achilles' heel in recent weeks has been a banged-up offensive line, but that unit kept it together in the first half, despite being down two starters.

Miami coach Adam Gase schemed his playmakers open. Miami jumped to a 17-0 lead. For the first three quarters, the Dolphins looked like the team they want to be, one that can overcome adversity, use its game-changing speed to scare defenses and unleash a ball-hawking defense to finish games off.

Overall, they responded with fight after last week’s 38-7 beatdown at New England.

“The last two games were completely different. We felt really good this game,” Tannehill said. “We got into a groove in the second quarter and even in the third for a little [while]. We felt good about our game plan and how we were attacking them.”

But even well-meaning Dolphins hope seems destined to crumble at some point, just as their offense did in Sunday's 27-17 loss.

Left tackle Laremy Tunsil left in the third quarter with a concussion, and Gase said that started the meltdown. Bengals coach Marvin Lewis said they saw “blood in the water.” Cincinnati (4-1) scored 27 consecutive points and 24 in the fourth quarter.

“That kind of shook us up a little bit. We didn’t bounce back from that very well,” Gase said. “They started teeing off on us.”

Tannehill also wasn’t willing to let the offensive line or the Dolphins' defense, which played well Sunday, fall on the sword.

“This is squarely on me and the offense. That’s my responsibility,” Tannehill said. “It all unraveled when the turnovers happened. That’s on me, and I have to find a way to eliminate those plays and get the ball in the end zone.”

Miami (3-2) never had much margin of error. They were getting a strong performance from their defense, which already has more interceptions (10) after five games than it did in 16 games in 2017 (nine).

“It’s sick, man. It’s sick. But we got to have the offense’s back,” said defensive tackle Davon Godchaux, who was a part of a unit that held the Bengals' offense to 13 points. “It’s hard. We were up 17-0, then they make two great defensive plays. It’s very tough. But we are what our record says we are.”

The Dolphins' offense scored more points for the Bengals (two defensive touchdowns) than it did for Miami (a touchdown and a field goal). But maybe this is what this Dolphins team is: good enough to beat anybody short of the top-echelon teams on their best days and bad enough to choke those seemingly secure games away.

Over the last two games, Tannehill has led the Dolphins to 10 offensive points in his 21 drives. That won't win you games against many teams in this league.

Yes, injuries have piled up tremendously and made it an uphill challenge for Tannehill to overcome. The Dolphins now have three injured starting offensive linemen (Tunsil, Josh Sitton and Daniel Kilgore).

But every NFL team has injuries, even significant ones, and the really good teams find ways to survive them.

That might be where we find our answer. The Dolphins aren’t a really good team yet, and it’s hard to trust that they’ll become one this year.